* Patch by Daniel Engström, 13 Nov 2002:

  Add support for i386 architecture and AMD SC520 board

* Patch by Pierre Aubert, 12 Nov 2002:
  Add support for DOS filesystem and booting from DOS floppy disk

1 files changed, 460 insertions, 0 deletions

diff --git a/cpu/i386/serial.c b/cpu/i386/serial.c
new file mode 100644
index 0000000..c0d2e8a
--- /dev/null
+++ b/cpu/i386/serial.c
@@ -0,0 +1,460 @@
+/*
+ * (C) Copyright 2002
+ * Daniel Engström, Omicron Ceti AB, daniel@omicron.se
+ * 
+ * (C) Copyright 2000
+ * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
+ *
+ * See file CREDITS for list of people who contributed to this
+ * project.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of
+ * the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
+ * MA 02111-1307 USA
+ */
+/*------------------------------------------------------------------------------+ */
+/*
+ * This source code has been made available to you by IBM on an AS-IS
+ * basis.  Anyone receiving this source is licensed under IBM
+ * copyrights to use it in any way he or she deems fit, including
+ * copying it, modifying it, compiling it, and redistributing it either
+ * with or without modifications.  No license under IBM patents or
+ * patent applications is to be implied by the copyright license.
+ *
+ * Any user of this software should understand that IBM cannot provide
+ * technical support for this software and will not be responsible for
+ * any consequences resulting from the use of this software.
+ *
+ * Any person who transfers this source code or any derivative work
+ * must include the IBM copyright notice, this paragraph, and the
+ * preceding two paragraphs in the transferred software.
+ *
+ * COPYRIGHT   I B M   CORPORATION 1995
+ * LICENSED MATERIAL  -  PROGRAM PROPERTY OF I B M
+ */
+/*------------------------------------------------------------------------------- */
+
+#include <common.h>
+#include <watchdog.h>
+#include <asm/io.h>
+#include <asm/ibmpc.h>
+
+#if CONFIG_SERIAL_SOFTWARE_FIFO
+#include <malloc.h>
+#endif
+
+#define UART_RBR    0x00
+#define UART_THR    0x00
+#define UART_IER    0x01
+#define UART_IIR    0x02
+#define UART_FCR    0x02
+#define UART_LCR    0x03
+#define UART_MCR    0x04
+#define UART_LSR    0x05
+#define UART_MSR    0x06
+#define UART_SCR    0x07
+#define UART_DLL    0x00
+#define UART_DLM    0x01
+
+/*-----------------------------------------------------------------------------+
+  | Line Status Register.
+  +-----------------------------------------------------------------------------*/
+#define asyncLSRDataReady1            0x01
+#define asyncLSROverrunError1         0x02
+#define asyncLSRParityError1          0x04
+#define asyncLSRFramingError1         0x08
+#define asyncLSRBreakInterrupt1       0x10
+#define asyncLSRTxHoldEmpty1          0x20
+#define asyncLSRTxShiftEmpty1         0x40
+#define asyncLSRRxFifoError1          0x80
+
+
+
+#if CONFIG_SERIAL_SOFTWARE_FIFO
+/*-----------------------------------------------------------------------------+
+  | Fifo
+  +-----------------------------------------------------------------------------*/
+typedef struct {
+	char *rx_buffer;
+	ulong rx_put;
+	ulong rx_get;
+} serial_buffer_t;
+
+volatile static serial_buffer_t buf_info;
+#endif
+
+
+static int serial_div (int baudrate )
+{
+	
+	switch (baudrate) {
+	case 1200:
+		return 96;
+	case 9600:
+		return 12;
+	case 19200:
+		return 6;
+	case 38400:
+		return 3;
+	case 57600:
+		return 2;
+	case 115200:
+		return 1;		
+	}
+	hang ();
+}
+
+
+/*
+ * Minimal serial functions needed to use one of the SMC ports
+ * as serial console interface.
+ */
+
+int serial_init (void)
+{
+	DECLARE_GLOBAL_DATA_PTR;
+
+	volatile char val;
+
+	int bdiv = serial_div(gd->baudrate);
+    
+
+	outb(0x80, UART0_BASE + UART_LCR);	/* set DLAB bit */
+	outb(bdiv, UART0_BASE + UART_DLL);	/* set baudrate divisor */
+	outb(bdiv >> 8, UART0_BASE + UART_DLM);/* set baudrate divisor */
+	outb(0x03, UART0_BASE + UART_LCR);	/* clear DLAB; set 8 bits, no parity */
+	outb(0x00, UART0_BASE + UART_FCR);	/* disable FIFO */
+	outb(0x00, UART0_BASE + UART_MCR);	/* no modem control DTR RTS */
+	val = inb(UART0_BASE + UART_LSR);	/* clear line status */
+	val = inb(UART0_BASE + UART_RBR);	/* read receive buffer */
+	outb(0x00, UART0_BASE + UART_SCR);	/* set scratchpad */
+	outb(0x00, UART0_BASE + UART_IER);	/* set interrupt enable reg */
+
+	return (0);
+}
+
+
+void serial_setbrg (void)
+{
+	DECLARE_GLOBAL_DATA_PTR;
+
+	unsigned short bdiv;
+	
+	bdiv = serial_div (gd->baudrate);
+
+	outb(0x80, UART0_BASE + UART_LCR);	/* set DLAB bit */
+	outb(bdiv&0xff, UART0_BASE + UART_DLL);	/* set baudrate divisor */
+	outb(bdiv >> 8, UART0_BASE + UART_DLM);/* set baudrate divisor */
+	outb(0x03, UART0_BASE + UART_LCR);	/* clear DLAB; set 8 bits, no parity */
+}
+
+
+void serial_putc (const char c)
+{
+	int i;
+
+	if (c == '\n')
+		serial_putc ('\r');
+
+	/* check THRE bit, wait for transmiter available */
+	for (i = 1; i < 3500; i++) {
+		if ((inb (UART0_BASE + UART_LSR) & 0x20) == 0x20)
+			break;
+		udelay (100);
+	}
+	outb(c, UART0_BASE + UART_THR);	/* put character out */
+}
+
+
+void serial_puts (const char *s)
+{
+	while (*s) {
+		serial_putc (*s++);
+	}
+}
+
+
+int serial_getc ()
+{
+	unsigned char status = 0;
+
+	while (1) {
+#if defined(CONFIG_HW_WATCHDOG)
+		WATCHDOG_RESET ();	/* Reset HW Watchdog, if needed */
+#endif	/* CONFIG_HW_WATCHDOG */
+		status = inb (UART0_BASE + UART_LSR);
+		if ((status & asyncLSRDataReady1) != 0x0) {
+			break;
+		}
+		if ((status & ( asyncLSRFramingError1 |
+				asyncLSROverrunError1 |
+				asyncLSRParityError1  |
+				asyncLSRBreakInterrupt1 )) != 0) {
+			outb(asyncLSRFramingError1 |
+			      asyncLSROverrunError1 |
+			      asyncLSRParityError1  |
+			      asyncLSRBreakInterrupt1, UART0_BASE + UART_LSR);
+		}
+	}
+	return (0x000000ff & (int) inb (UART0_BASE));
+}
+
+
+int serial_tstc ()
+{
+	unsigned char status;
+
+	status = inb (UART0_BASE + UART_LSR);
+	if ((status & asyncLSRDataReady1) != 0x0) {
+		return (1);
+	}
+	if ((status & ( asyncLSRFramingError1 |
+			asyncLSROverrunError1 |
+			asyncLSRParityError1  |
+			asyncLSRBreakInterrupt1 )) != 0) {
+		outb(asyncLSRFramingError1 |
+		      asyncLSROverrunError1 |
+		      asyncLSRParityError1  |
+		      asyncLSRBreakInterrupt1, UART0_BASE + UART_LSR);
+	}
+	return 0;
+}
+
+
+#if CONFIG_SERIAL_SOFTWARE_FIFO
+
+void serial_isr (void *arg)
+{
+	int space;
+	int c;
+	const int rx_get = buf_info.rx_get;
+	int rx_put = buf_info.rx_put;
+
+	if (rx_get <= rx_put) {
+		space = CONFIG_SERIAL_SOFTWARE_FIFO - (rx_put - rx_get);
+	} else {
+		space = rx_get - rx_put;
+	}
+	while (serial_tstc ()) {
+		c = serial_getc ();
+		if (space) {
+			buf_info.rx_buffer[rx_put++] = c;
+			space--;
+		}
+		if (rx_put == CONFIG_SERIAL_SOFTWARE_FIFO)
+			rx_put = 0;
+		if (space < CONFIG_SERIAL_SOFTWARE_FIFO / 4) {
+			/* Stop flow by setting RTS inactive */
+			outb(inb (UART0_BASE + UART_MCR) & (0xFF ^ 0x02),
+			      UART0_BASE + UART_MCR);
+		}
+	}
+	buf_info.rx_put = rx_put;
+}
+
+void serial_buffered_init (void)
+{
+	serial_puts ("Switching to interrupt driven serial input mode.\n");
+	buf_info.rx_buffer = malloc (CONFIG_SERIAL_SOFTWARE_FIFO);
+	buf_info.rx_put = 0;
+	buf_info.rx_get = 0;
+
+	if (inb (UART0_BASE + UART_MSR) & 0x10) {
+		serial_puts ("Check CTS signal present on serial port: OK.\n");
+	} else {
+		serial_puts ("WARNING: CTS signal not present on serial port.\n");
+	}
+
+	irq_install_handler ( VECNUM_U0 /*UART0 *//*int vec */ ,
+			      serial_isr /*interrupt_handler_t *handler */ ,
+			      (void *) &buf_info /*void *arg */ );
+
+	/* Enable "RX Data Available" Interrupt on UART */
+	/* outb(inb(UART0_BASE + UART_IER) |0x01, UART0_BASE + UART_IER); */
+	outb(0x01, UART0_BASE + UART_IER);
+	/* Set DTR active */
+	outb(inb (UART0_BASE + UART_MCR) | 0x01, UART0_BASE + UART_MCR);
+	/* Start flow by setting RTS active */
+	outb(inb (UART0_BASE + UART_MCR) | 0x02, UART0_BASE + UART_MCR);
+	/* Setup UART FIFO: RX trigger level: 4 byte, Enable FIFO */
+	outb((1 << 6) | 1, UART0_BASE + UART_FCR);
+}
+
+void serial_buffered_putc (const char c)
+{
+	/* Wait for CTS */
+#if defined(CONFIG_HW_WATCHDOG)
+	while (!(inb (UART0_BASE + UART_MSR) & 0x10))
+		WATCHDOG_RESET ();
+#else
+	while (!(inb (UART0_BASE + UART_MSR) & 0x10));
+#endif
+	serial_putc (c);
+}
+
+void serial_buffered_puts (const char *s)
+{
+	serial_puts (s);
+}
+
+int serial_buffered_getc (void)
+{
+	int space;
+	int c;
+	int rx_get = buf_info.rx_get;
+	int rx_put;
+
+#if defined(CONFIG_HW_WATCHDOG)
+	while (rx_get == buf_info.rx_put)
+		WATCHDOG_RESET ();
+#else
+	while (rx_get == buf_info.rx_put);
+#endif
+	c = buf_info.rx_buffer[rx_get++];
+	if (rx_get == CONFIG_SERIAL_SOFTWARE_FIFO)
+		rx_get = 0;
+	buf_info.rx_get = rx_get;
+
+	rx_put = buf_info.rx_put;
+	if (rx_get <= rx_put) {
+		space = CONFIG_SERIAL_SOFTWARE_FIFO - (rx_put - rx_get);
+	} else {
+		space = rx_get - rx_put;
+	}
+	if (space > CONFIG_SERIAL_SOFTWARE_FIFO / 2) {
+		/* Start flow by setting RTS active */
+		outb(inb (UART0_BASE + UART_MCR) | 0x02, UART0_BASE + UART_MCR);
+	}
+
+	return c;
+}
+
+int serial_buffered_tstc (void)
+{
+	return (buf_info.rx_get != buf_info.rx_put) ? 1 : 0;
+}
+
+#endif	/* CONFIG_SERIAL_SOFTWARE_FIFO */
+
+
+#if (CONFIG_COMMANDS & CFG_CMD_KGDB)
+/*
+  AS HARNOIS : according to CONFIG_KGDB_SER_INDEX kgdb uses serial port
+  number 0 or number 1
+  - if CONFIG_KGDB_SER_INDEX = 1 => serial port number 0 :
+  configuration has been already done
+  - if CONFIG_KGDB_SER_INDEX = 2 => serial port number 1 :
+  configure port 1 for serial I/O with rate = CONFIG_KGDB_BAUDRATE
+*/
+#if (CONFIG_KGDB_SER_INDEX & 2)
+void kgdb_serial_init (void)
+{
+	DECLARE_GLOBAL_DATA_PTR;
+
+	volatile char val;
+	bdiv = serial_div (CONFIG_KGDB_BAUDRATE);
+
+	/*
+	 * Init onboard 16550 UART
+	 */
+	outb(0x80, UART1_BASE + UART_LCR);	/* set DLAB bit */
+	outb(bdiv & 0xff), UART1_BASE + UART_DLL);	/* set divisor for 9600 baud */
+	outb(bdiv >> 8), UART1_BASE + UART_DLM);	/* set divisor for 9600 baud */
+	outb(0x03, UART1_BASE + UART_LCR);	/* line control 8 bits no parity */
+	outb(0x00, UART1_BASE + UART_FCR);	/* disable FIFO */
+	outb(0x00, UART1_BASE + UART_MCR);	/* no modem control DTR RTS */
+	val = inb(UART1_BASE + UART_LSR);	/* clear line status */
+	val = inb(UART1_BASE + UART_RBR);	/* read receive buffer */
+	outb(0x00, UART1_BASE + UART_SCR);	/* set scratchpad */
+	outb(0x00, UART1_BASE + UART_IER);	/* set interrupt enable reg */
+}
+
+
+void putDebugChar (const char c)
+{
+	if (c == '\n')
+		serial_putc ('\r');
+
+	outb(c, UART1_BASE + UART_THR);	/* put character out */
+
+	/* check THRE bit, wait for transfer done */
+	while ((inb(UART1_BASE + UART_LSR) & 0x20) != 0x20);
+}
+
+
+void putDebugStr (const char *s)
+{
+	while (*s) {
+		serial_putc(*s++);
+	}
+}
+
+
+int getDebugChar (void)
+{
+	unsigned char status = 0;
+
+	while (1) {
+		status = inb(UART1_BASE + UART_LSR);
+		if ((status & asyncLSRDataReady1) != 0x0) {
+			break;
+		}
+		if ((status & ( asyncLSRFramingError1 |
+				asyncLSROverrunError1 |
+				asyncLSRParityError1  |
+				asyncLSRBreakInterrupt1 )) != 0) {
+			outb(asyncLSRFramingError1 |
+			     asyncLSROverrunError1 |
+			     asyncLSRParityError1  |
+			     asyncLSRBreakInterrupt1, UART1_BASE + UART_LSR);
+		}
+	}
+	return (0x000000ff & (int) inb(UART1_BASE));
+}
+
+
+void kgdb_interruptible (int yes)
+{
+	return;
+}
+
+#else	/* ! (CONFIG_KGDB_SER_INDEX & 2) */
+
+void kgdb_serial_init (void)
+{
+	serial_printf ("[on serial] ");
+}
+
+void putDebugChar (int c)
+{
+	serial_putc (c);
+}
+
+void putDebugStr (const char *str)
+{
+	serial_puts (str);
+}
+
+int getDebugChar (void)
+{
+	return serial_getc ();
+}
+
+void kgdb_interruptible (int yes)
+{
+	return;
+}
+#endif	/* (CONFIG_KGDB_SER_INDEX & 2) */
+#endif	/* CFG_CMD_KGDB */
+